d-p Hybridization-Induced “Trapping–Coupling–Conversion” Enables High-Efficiency Nb Single-Atom Catalysis for Li–S Batteries

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(3), P. 1728 - 1739

Published: Jan. 14, 2023

Single-atom catalysts have been paid more attention to improving sluggish reaction kinetics and anchoring polysulfide for lithium-sulfur (Li-S) batteries. It has demonstrated that d-block single-atom elements in the fourth period can chemically interact with local environment, leading effective adsorption catalytic activity toward lithium polysulfides. Enlightened by theoretical screening, first time, we design novel Nb improved sulfur immobilization catalyzation. Calculations reveal Nb-N4 active moiety possesses abundant unfilled antibonding orbitals, which promotes d-p hybridization enhances capability polysulfides via a "trapping-coupling-conversion" mechanism. The Nb-SAs@NC cell exhibits high capacity retention of over 85% after 1000 cycles, superior rate performance 740 mA h g-1 at 7 C, competitive areal 5.2 mAh cm-2 (5.6 mg cm-2). Our work provides new perspective extend cathodes enabling high-energy-density Li-S

Language: Английский

---

Recent Progress of Hollow Carbon Nanocages: General Design Fundamentals and Diversified Electrochemical Applications

Advanced Science, Journal Year: 2023, Volume and Issue: 10(7)

Published: Jan. 1, 2023

Abstract Hollow carbon nanocages (HCNCs) consisting of sp 2 shells featured by a hollow interior cavity with defective microchannels (or customized mesopores) across the shells, high specific surface area, and tunable electronic structure, are quilt different from other nanocarbons such as nanotubes graphene. These structural morphological characteristics make HCNCs new platform for advanced electrochemical energy storage conversion. This review focuses on controllable preparation, regulation, modification HCNCs, well their functions applications materials electrocatalytic conversion materials. The metal single atoms‐functionalized structures properties summarized systematically deeply. research challenges trends also envisaged deepening extending study application this material. development multifunctional carbon‐based composite provides idea method improving density, power volume performance devices.

Language: Английский

---

Long-Lasting Zinc–Iodine Batteries with Ultrahigh Areal Capacity and Boosted Rate Capability Enabled by Nickel Single-Atom Electrocatalysts

Nano Letters, Journal Year: 2023, Volume and Issue: 23(11), P. 5272 - 5280

Published: June 1, 2023

Zinc-iodine (Zn-I2) batteries have garnered significant attention for their high energy density, low cost, and inherent safety. However, several challenges, including polyiodide dissolution shuttling, sluggish iodine redox kinetics, electrical conductivity, limit practical applications. Herein, we designed a highly efficient electrocatalyst Zn-I2 by uniformly dispersing Ni single atoms (NiSAs) on hierarchical porous carbon skeletons (NiSAs-HPC). In situ Raman analysis revealed that the conversion of soluble polyiodides (I3- I5-) was significantly accelerated using NiSAs-HPC because remarkable electrocatalytic activity NiSAs. The resulting with NiSAs-HPC/I2 cathodes delivered exceptional rate capability (121 mAh g-1 at 50 C), ultralong cyclic stability (over 40 000 cycles C). Even under 11.6 mg cm-2 iodine, still exhibited an impressive capacity retention 93.4% 141 after 10 C.

Language: Английский

---

Wide-Temperature Operation of Lithium–Sulfur Batteries Enabled by Multi-Branched Vanadium Nitride Electrocatalyst

ACS Nano, Journal Year: 2023, Volume and Issue: 17(12), P. 11527 - 11536

Published: June 8, 2023

High-performance lithium-sulfur (Li-S) batteries that can work normally under harsh conditions have attracted tremendous attention; however, the sluggish reaction kinetics of polysulfide conversions at low temperatures as well notorious shuttling high remain to be resolved. Herein, a multibranched vanadium nitride (MB-VN) electrocatalyst has been designed and deployed for Li-S batteries. Both experimental (time-of-flight secondary ion mass spectroscopy adsorption tests) theoretical results verify strong chemical capability electrocatalytic activity MB-VN with respect polysulfides. Moreover, in situ Raman characterization manifests effective inhibition by electrocatalyst. Using MB-VN-modified separators, deliver an excellent rate (707 mAh g-1 3.0 C) great cyclic stability (678 after 400 cycles 1.0 room temperature. With 6.0 mg cm-2 sulfur lean electrolyte volume ∼6 μL mgs-1, exhibit areal capacity 5.47 cm-2. Even over wide temperature range (-20 +60 °C), still maintain stable performance current rates. This demonstrates metal based electrocatalysts realize low-/high-temperature-tolerant

Language: Английский

---

Fe/Co dual metal catalysts modulated by S-ligands for efficient acidic oxygen reduction in PEMFC

Science Advances, Journal Year: 2023, Volume and Issue: 9(23)

Published: June 9, 2023

Here, we report a conceptual strategy for introducing spatial sulfur (S)–bridge ligands to regulate the coordination environment of Fe-Co-N dual-metal centers (Spa-S-Fe,Co/NC). Benefiting from electronic modulation, Spa-S-Fe,Co/NC catalyst showed remarkably enhanced oxygen reduction reaction (ORR) performance with half-wave potential ( E 1/2 ) 0.846 V and satisfactory long-term durability in acidic electrolyte. Combined experimental theoretical studies revealed that excellent ORR activity remarkable stability observed is attributable optimal adsorption-desorption oxygenated intermediates achieved through charge-modulation bimetallic by S-bridge ligands. These findings provide unique perspective local catalysts dual-metal-centers optimize their electrocatalytic performance.

Language: Английский

---

Development of Synergistically Efficient Ni–Co Pair Catalytic Sites for Enhanced Polysulfide Conversion in Lithium–Sulfur Batteries

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(37)

Published: March 29, 2024

Abstract The performance of Lithium–sulfur (Li–S) batteries is constrained by the migration lithium polysulfide (LiPS), slow conversion LiPS, and significant reaction barrier encountered during precipitation/dissolution Li 2 S throughout discharge/charge cycle. In this contribution, study presents Ni–Co dual‐atom catalytic sites on hollow nitrogen‐doped carbon (NiCoNC). Theoretical calculations experimental data reveal that catalysts (DACs) accelerate kinetic LiPSs facilitate formation/decomposition discharging charging, which minimizes LiPS migration. Consequently, utilization S/NiCoNC cathodes manifests a substantial initial capacity 1348.5 mAh g −1 at 0.1 C, exceptional cycling stability with an average degradation rate 0.028% per cycle over 900 cycles 0.5 noteworthy capability 626 C. Electrodes higher sulfur loading 4.5 mg cm −2 low electrolyte/sulfur ratio 8 µL exhibit specific capacities up to 1236 as well retention 494.2 after 200 0.2 This effectively showcases potential DACs for cathodes, thereby enhancing overall Li–S batteries.

Language: Английский

---

Vanadium as Auxiliary for Fe–V Dual-Atom Electrocatalyst in Lithium–Sulfur Batteries: “3D in 2D” Morphology Inducer and Coordination Structure Regulator

ACS Nano, Journal Year: 2023, Volume and Issue: 17(17), P. 17405 - 17416

Published: Aug. 25, 2023

The undesirable shuttling behavior, the sluggish redox kinetics of liquid-solid transformation, and large energy barrier for decomposition Li2S have been recognized problems impeding practical application lithium-sulfur batteries. Herein, inspired by spectacular catalytic activity Fe/V center in bioenzyme nitrogen/sulfur fixation, we design an integrated electrocatalyst comprising N-bridged Fe-V dual-atom active sites (Fe/V-N7) dispersed on ingenious "3D 2D" carbon nanosheets (denoted as DAC), which vanadium induces laminar structure regulates coordination configuration centers simultaneously, realizing redistribution 3d-orbital electrons Fe centers. high coupling/conjunction between 3d S 2p shows strong affinity enhanced reactivity DAC-Li2Sn (1 ≤ n 8) systems. Thus, DAC presents strengthened chemisorption ability toward polysulfides significantly boosts bidirectional sulfur reaction kinetics, evidenced theoretically experimentally. Besides, well-designed morphology enables uniform distribution, facilitated electron transfer, abundant exposure. Therefore, assembled Li-S cells present outstanding cycling stability (637.3 mAh g-1 after 1000 cycles at 1 C) rate capability (711 4 under content (70 wt %).

Language: Английский

---

Atomically Dispersed Fe–N₄ and Ni–N₄ Independent Sites Enable Bidirectional Sulfur Redox Electrocatalysis

Nano Letters, Journal Year: 2023, Volume and Issue: 23(9), P. 4000 - 4007

Published: April 26, 2023

Single-atom catalysts (SACs) with high atom utilization and outstanding catalytic selectivity are useful for improving battery performance. Herein, atomically dispersed Ni-N4 Fe-N4 dual sites coanchored on porous hollow carbon nanocages (Ni-Fe-NC) fabricated deployed as the sulfur host Li-S battery. The conductive matrix promotes electron transfer also accommodates volume fluctuation during cycling. Notably, d band center of Fe in site demonstrates strong polysulfide affinity, leading to an accelerated reduction reaction. Meanwhile, Li2S delivers a metallic property S 2p density states around Femi energy level, enabling low evolution reaction barrier. effect Ni-Fe-NC endows cathode density, prolonged lifespan, polarization.

Language: Английский

---

Relay-Type Catalysis by a Dual-Metal Single-Atom System in a Waste Biomass Derivative Host for High-Rate and Durable Li–S Batteries

ACS Nano, Journal Year: 2024, Volume and Issue: 18(21), P. 13468 - 13483

Published: May 13, 2024

An environmental-friendly and sustainable carbon-based host is one of the most competitive strategies for achieving high loading practicality Li–S batteries. However, polysulfide conversion reaction kinetics still limited by nonuniform or monofunctional catalyst configuration in carbon host. In this work, we propose a catalysis mode based on "relay-type" co-operation adjacent dual-metal single atoms high-rate durable A discarded sericin fabric-derived porous N-doped with stacked schistose structure prepared as high-loading sulfur (84 wt %) facile ionothermal method, which further enables uniform anchoring Fe/Co atoms. This multifunctional superior lithiophilic–sulfiphilic electrocatalytic capabilities contributed single-atom modulation effects different stages liquid polysulfides solid Li2S2/Li2S, leading to suppression "shuttle effect", alleviation nucleation decomposition barriers Li2Sx, acceleration kinetics. The corresponding batteries exhibit specific capacity 1399.0 mA h g–1, performance up 10 C, excellent cycling stability over 1000 cycles. They can also endure 8.5 mg cm–2 lean electrolyte condition yield an areal 8.6 cm–2. work evidentially demonstrates potential waste biomass reutilization coupled design system practical energy density.

Language: Английский

---

Ni Single‐Atom Bual Catalytic Electrodes for Long Life and High Energy Efficiency Zinc‐Iodine Batteries

Small, Journal Year: 2024, Volume and Issue: 20(26)

Published: Jan. 17, 2024

Abstract Zinc‐iodine batteries (Zn‐I2) are extremely attractive as the safe and cost‐effective scalable energy storage system in stationary applications. However, inefficient redox kinetics “shuttling effect” of iodine species result unsatisfactory efficiency short cycle life, hindering their commercialization. In this work, Ni single atoms highly dispersed on carbon fibers is designed synthesized anchoring sites dual catalysts for Zn‐I2 batteries, successfully inhibit shuttling boost reaction kinetics. Theoretical calculations indicate that reinforced d‐p orbital hybridization charge interaction between single‐atoms effectively enhance confinement species. also accelerate conversion reactions with tailored bonding structure I─I bonds reduced barrier Consequently, high‐rate performance (180 mAh g −1 at 3 A ), cycling stability (capacity retention 74% after 5900 cycles) high (90% ) achieved. The work provides an effective strategy development hosts catalytic activity batteries.

Language: Английский

---